Pump mechanism



July 19, 1932. 4 E, w, DILG 1,868,161

PUMP MECHANISM Filed Feb. 20. 1930 INVENTOR ATTORNEYS.

Patented July 19, 1932` UNITED 'STATES PATENT ori-lcs EARL W. DILG, OE DETROIT, MICHIGAN; ASSIGNOB TO EVANS APPLIANGE COIIANY,

` A. CORPORATION OF MICHIGAN Pm IECHANISH Application illed February 20, 1930. Serial No. 429,867.

This invention relates to fuel supply devices for internal combustion engines. The main objects of this invention are to provide an improved Huid pump and dis- 5 tributin means for the discharge' thereof; to provi.' e a-unitary structure of pump and' distributor havinga common drive shaft; to provide improved means for varying the pressure in the pump discharge, so as' to' vary fn the velocity and consequently the amount of the distributed fluid; and to provide a com'-l pact unit of simple 'construction which will draw the-fuel from the supply tank and distribute it to the various cylindersof amotor 1,', in variable quantities as desired.

' An illustrative embodiment of this invention is shown in the accompanying drawing, in which Fig. 1 is a vertical, medial, longitudinal,

2n Sectional view of my improved unit.

Fig. 2 is a sectional view of the same taken on the line 2-2 of Fig. 1, 'looking in the direction indicated b the arrows.

Fig. 3 is a sectiona view of the same taken on the line 3.-3 of Fig. 2,' looking in the direction indicatedby'the arrows.

. Fig. 4 is a sectional view of the same taken on the line 4-4 of Fi 1, looking in the direction indicated by t e arrows.

Heretofore inthe construction of fuel supply systems utilizing the injection principle,

-it has been customary to have injection units which have pistonplungers therein, which piston plungers are arran ed to have a va-- 1 riable stroke, that is, lengt of travel. This has been necessary for the purpose of increasing or decreasing the amount -of fuel supplied to the engine cylinder to meet the varying` conditions from' idling to th'at 'of fullepower. 4 These systems have all been more or less unsatisfactory due to the fact that a suicient range was not obtainable andconsequently the majority-of the successfully operating injection principle types of fuel systemsl are confined in their use'to engines which run at substantiall constant speedA under all con` ditions, suc as airplane and marine motor engines. Such systems arenot at all adaptable for use in automobiles where the speed and power output of the motor is constantly changing and has to varybetween wide limits. 1

In the construction shown in the drawing a housing or casing 5f'is providedwith a pumping cylinder 6, within which is housed a rotor piston 7 rigidly secup'd to a drive shaft 8 by a key 9. The shaft8 is journaled 'in the housin 5 andin thefparticular unit shownl exten into and through another housing 10 which has a rotary lubricating oil pump 11 therein. v

\The pump housing. 5 is provided with intake and discharge passageways 12 and 13, respectively, which communicate with" the pumping cylinder 6. A byass 14 is formed 1n the housing 5 for provi 'ng eommumcation between the discharge way 13 and the intake passageway 12. A all valve 15 for controlling the ow of fluid through the by-pass 14, is normally, .yieldingly urged ltoward its seat by\ a hehcal compression spring 16. One end of the spring 16 fits upon the ball 15 and the other en Athereof lfits within an inverted cup-shaped plunger 17 slidably mounted within a c hndrical passageway 18, which houses the ll valve and spring assembly. y '-2 Means are'provided for varying the tension on the spring 16 and com rise a vertically disposed pin or stem 19 axially slidabl in a stufling box 20, which 'is threaded intoY an upstanding liollwboss 21 inte ally formed on the housing 5. The stuliing` o'x 20 carries a packing gland 22 for preventing the escape of fluid around the stem 19 and a cap nut 23 e is threaded on the outer end of the stuing box for urging a packing gland ring 24 downwardly against the packing 22.

The lower end of the stem 19 is riveted to the inverted cup 17 and the upper end therecured thereto by a pin 26. A helical compresaov sion spring `27 surrounds the outer projecting end of the stem 19 with one end thereof seated on the top side ofthe cap nut 23 and the other end thereof bearing against the` under side of the Washer 25.

Means are provided for axially moving the stem 19 downwardly against the action of the compression spring 27 so as to compress the valve spring 16, and comprise a'bell crank lever'28, pivoted on-the upstanding-end of a bracket arm 28A. One arm'29 of the bell crank 28 is adapted to be connected to the carburetor throttle and the other arm 30 thereof terminates in a head 31. The head 31 has a convex face which rests upon and bears against the top end of the stem 19.

Means are provided for distributing the fluid discharged by the pump to a plurality of sources such as the cylinders of an internal combustion engine, and comprisev a distribu- .tor valve casing 32 which is provided with an annular groove 33 on the inner face thereof. The groove 33 communicates through a passageway 34 with an axially disposed passageway 35 of the pumpcasing 5, which in turn communicates with ,the discharge passageway 13. The casing 32 is adapted to fit against the outer side or face of the pump casing 5 in fluid-tight Contact therewith so that it closes the groovej 33 and forms an `annular passageway which `isdisposed in concentric relation with respect tothe axis of if the drive shaft 8.

` In the particular embodiment shown, the fluid is to be distributed to four different sources, such as a four-cylinder engine, but any number may be provided for in the same manner. The distributor casing 32 as shown,

is provided with four axially disposed passageways 36which are disposed equi-distantly circumferentially of the casing. The inner ends of the passageways 36 communicate with the annular passageway 33, and the outer ends may be threaded as shown at 37 to receive suitable pipe connections variousv cylinders.

Means are provided for controlling the iow of fluid through these assageways 36 and comprise an equal nu'm er of valves in the form of pins 38'which are axially slidable` in radially extending passageways 39.

passageways 39 intersect and are of larger diameter than the fuel passageways 36. Each of the pins 38 has an annular groove 40 turned in theouter periphery thereof which permits f the passage of fluid .around the valve pinwhen said groove is in registry with the fuel passageway 36 by reason of its smaller cross sectional area. v y

Means are provided for moving the valve pins 38 outwardly radially of the deviceand ,comprisea cam 41 mounted on a shaft head which lead to thek The 42. The head 42 is journaled in' a bushing 43 ment with the shaft 8 and the adjacent ends thereof have interittin-g tongue and groove connections y so that the shaft 8 drives the shaft 42. The cam 41 is preferably mounted on the shaft head 42 by a plurality of V- shaped teeth or serrations so that its position relativel to the shaft may be readily adjusted by slipping the cam axially off of its serrated mounting and replacing in a different angular position. y i

Means are provided for normally holding the valve pins 38 inwardly in contact with the cam 41 and comprise passageways 46 and 47 which provide communication between the fluid discharge passageway 36 and the outer end of the valve pin passageway 39 so that fluid pressure in the discharge of the pump will be exerted against the outer end of the valve pin at all times.

The fuel pump housing 5, lubricating oil pump housing 10, distributor housing 32 and outer closure cap 44 are all tied together and held in assembled relationship by a plurality of axially extending cap screws 48 which are threaded into the housing 10, and 'the' heads of which bear against the outer side of the closure cap 44.

In the operation of this unit the intake 12- of the fuel pump is connected to a suitable source o f supply and the shaft 8 connected to a suitable source of power so that it may be rotated. Usually this connection is to the cam shaft of the internal combustion engine through-suitable gears.y When this connection has been made the cam 41 is adjusted on its mounting so as to be in proper timed relationship with respect to the cylinders of the engine whereby fuel will be discharged to said cylinders at the appropriate times/with relation to the opening and closing of the engine cylinder valves. E

The normal output of the fuel pump is considerably in excess of the f iuid permitted to pass by the valve pins 38, such excess escaping around the by-pass ball valve 15 and returningu through the passageway 14 tothe intake side of the pump. The arrangement is preferably such that with the by-pass valve spring 16Su in the position shown in Fig. 4 of the drawing, only suflicient fluid will be discharged through the passageways 36 to cause the internal combustion motor to idle, the remainder of the fuel uel-pump.

When it is desired to speed up the motor by-p'assing within the' spring 16. This increased pressure on the spring 16 will in turn increase the pressure of the fluid in the discharge passageways of the pump, thereby causing a proportionately greater amount of fuel to pass by the valve pins 38 during the same period of opening. As the pressure within the pump is increased the amount of Huid fuel discharged through the passageways 36 will be proportionately increased. The strength of the by-pass valve spring and the contour of the cam 41 may be varied to meet the requirements of diiierent engines.`

Although but one speciiic embodiment of this invention has been herein shown and described, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the followin claims 1. In a fluid pump and distributing apparatus, the combination of a housing having a pumping cylinder therein, intake and discharge passageways in said housing communicating with said pumping cylinder, a shaft journaled in said housing, a rotor piston on said shaft for said pumping cylinder, a valve pin passageway intersectin said discharge passageway, a valve pin s idable in said valve pin 1passageway, said pin normally closing said discharge passagewayfa portion of said lpin being of less cross sectional area than the remainder for permitting the passage of iiuid thereby when in registry with said fluid discharge passageway, a passagewa providing communication ben tween said uid discharge passageway and the passageway atl one end of said valve pin for moving said pin in one direction byiluid pressure, and a cam driven by said pump shaft for moving said pin in the opposite direction.

2. In a fluid pump and distributing apparatus, the combination of a housing havin a pumping cylinder therein, a shaft journad in said housing, a rotor piston on said shaft for said pumping cylinder, intake and discharge passageways in said housing communicating with said pumping c linder, said housing having a plurality of ranch fluid passageways concentrically arranged with .respect to the axis of said shaft and circumferentially spaced therearound, a plurality of radially extending valve pin passageways in said housing intersecting said fluid passageways, cylindrical valve pins axially slidable in said pin passagewa s, said pins normallyelosing said branch uid assageways, a portion of each of said pins lbeing of less cross sectional area than the remainder for permitting the passage of fluid thereby when in registry with its fluid passageway,'pas sageways in said housing providing communication between said pump discharge and the outer ends of said valve in passageways for-movingv said pins inwar l by fluid pressure, and a cam on said shaft or moving said pins outwardly to open said valves.

3. In a uid pump and distributing apparatus, the combination of a housing having apumping cylinder, therein, a shaft journaed in said housing, a rotor iston on said shaft for said pumping cylin er, intake and discharge passageways in said housing communicating with said cylinder, a by-pass providing communication between said intake and discharge passa eways, a valve for ,controlling the passage o liuid through said by-pass, yielding means normally urging said valve toward a closed position, a valve normally closing said pump discharge assa eway, means ope-rated by said pump s aft or opening said valve a constant interval in relation to the rotation of said pump rotor, and

means for varying the pressure of said bypass, valve yielding means to vary the pressure in said pump 'discharge and thereby vary the amount of fluid iowing past said discharge valve.

v 4. In a fluid' pump and distributing apparatus, the combination of ahousing having a pumping cylinder therein, 4a. shaftV journaled in said housing, a rotor piston on said 4 shaft for said pumping cylinder, intake and` discharge passageways in said housing communicating with said cylinder, a by-pass procommunication' between said intake vidin and ischarge passageways, a valve for con- V,trolling ythe passage of uid through said by-pass, a ring normally urging said valve toward a c osed position, a valve normally` closing said pump discharge ptassageway, a cam driven by said pump sha for opening said discharge valve a constant interval in relation to the rotation of said pump rotor,

and throttle means for varying the tensionon said 'by-pass valve spring to vary the ressure in said pump discharge and therey vary the quantity of fluid flowing past said dischar valve. .t

5. In a fiuid pump and distributing apparatus, the combination of a housing having a pumping cilinder therein, a shaft Vjourynaled in said casing, a rotor piston on said shaft for said pumping cylinder, intake and discharge passageways in said housing communicating with, said pumping c linder, said housing having a pliralit of ranch fluid passageways, concentrical y arranged with respect to the axis of said shaft and circumferentially spaced therearound, said passageways operatively associated withan annular passageway disposed adjacent the ends thereof, a pluralityI of radially extendingvalves in the passageways insaid housin intersectv ing said concentrically arrange passa eways, cylindrical valve ins axially slidale insaid assageways, said)pins normally closingsai branch uidpassageways, a portion of each pin being of less'cross sectional area than the remainder for permitting the passage of fuel thereby when in reglstry with the fiuid passageway, passageways in said 5 housing providing communication between said pump discharge and the outer ends of said valve passageways for moving said pins Vinwardly by fluid pressure and a cam on said` shaft adjacent said rotor for moving said 19 pins outwardly for movin said valve.

- EAizL W. DILG. 

